Project Summary/Abstract This application outlines a research project to measure glyphosate exposure among pregnant women and a training plan to transition Dr. Curl from a junior faculty member to a fully independent investigator. Under the mentorship of Dr. Bruce Lanphear, Dr. Richard Fenske, and Dr. Julia Oxford, and with the advice and expertise of Dr. Lianne Sheppard, Dr. Don Morishita, and Dr. Michael Antoniou, this plan will provide training opportunities in birth cohort study design and implementation, exposure science, and glyphosate toxicity and use. This training plan will further provide an on?going network of collaborators, mentors and advisors, which will be critical to Dr. Curl's aim of attaining future R01 funding and building a sustained research agenda. Dr. Curl's research sits at the intersection between agriculture and health. Her long?term goal is to become an expert in assessing dietary exposure to agricultural pesticides, and to contribute to our overall understanding of the effect of such exposure on human health. This research project focuses on human exposure to glyphosate, the single most commonly applied agricultural chemical in the world. Glyphosate has been declared a probable human carcinogen by the International Agency for Research on Cancer and several recent toxicological studies have further suggested potential neurologic and developmental effects of glyphosate exposure at environmentally?relevant levels. However, despite its extensive use, frequent presence in food and environmental media, and potential toxicity, current exposure levels in human populations are not well documented. This proposed study aims to assess glyphosate exposure among a cohort of pregnant women and to quantify the relative contribution of agricultural and dietary sources of this exposure. Specifically, this project proposes to utilize an existing repository of urine samples previously collected from pregnant women to develop and validate a longitudinal urinary biomonitoring strategy for glyphosate assessment that will accommodate large within?individual exposure variation. This biomonitoring strategy will then be employed within a cohort of 40 pregnant women, recruited from urban areas >10 miles from the nearest glyphosate?treated field and agricultural areas <1 mile from the nearest glyphosate?treated field. It is hypothesized that women living near treated fields will have higher exposures than those living further away. These participants will then take part in a week?long randomized dietary intervention, in which half will receive exclusively organic food (grown without the use of synthetic pesticides, including glyphosate) and half will receive conventional food. It is hypothesized that there will be a reduction in glyphosate exposure among all participants randomized to the organic diet, but that the effect of the dietary intervention will be modified by residential location. This study will fill a critical gap in our understanding of the magnitude of glyphosate exposure in a potentially vulnerable population. It will further serve to quantify the relative contribution of dietary and environmental sources to glyphosate exposure in a non?occupationally exposed cohort.